This invention relates to a disposable feminine hygiene article having back-attached wings with adhesive to help secure the article to an undergarment, along with the adhesive areas on the main body portion of the article.
Disposable feminine hygiene articles, which are understood here in to include sanitary napkins, pantiliners, and incontinence pads, feature a main body portion comprising an absorbent material mounted on an impervious backing sheet, the main body portion being bounded by a peripheral edge. (As used herein, xe2x80x9cperipheral edgexe2x80x9d refers to the extreme outside edge of the main body, however that edge happens to have been formed.) Frequently, such articles further include attachment wings or flaps contiguously extending from said backing sheet from opposite sides thereof. Because portions of both the backing sheet and the wings support adhesive areas, when the article is placed with the backing sheet in contact with one side of the crotch area of an undergarment, and the wings are wrapped around the other side of the crotch area, the two opposing adhesive areas hold the article in proper location on both sides of the undergarment.
Such wings are either contiguous extensions of the backing sheet, in which case they hinge and fold primarily about said peripheral edge of the main body portion, or, they are hingedly attached to the backing sheet along a fold line located inside the peripheral edge of the main body portion, hereinafter, xe2x80x9cback-attachedxe2x80x9d. A preferred manner of constructing the latter is to form the wings as a contiguous extension of the backing sheet, and then to fold them about the peripheral edge and adhesively secure a portion of the wing to a portion of the backing sheet inside the peripheral edge. This is preferred because it biases the wings to fold back towards the main body portion, exactly as the user does when wrapping the wings about an interposed undergarment. It has been found that such a bias renders easier the wrapping of the wings about the undergarment. Indeed, in the absence of the bias so provided, the wings may have a tendency to unfold and pull their adhesive areas off the undergarment.
Nevertheless, the helpful bias noted above has its own disadvantage. The adhesive areas on both the backing sheet and the wings are temporarily covered by release paper until the user is ready to install the article. However, once the release paper is removed, if the adhesive area of a wing inadvertently contacts directly the adhesive area of the backing sheet, the two stick together so well (in the absence of the intended undergarment), that they cannot be pulled apart without damaging the article. The noted bias of the wings towards the backing sheet has the disadvantage of making such inadvertent contact more, rather than less, likely.
Thus, there has been a need prior to this invention to prevent wing adhesive areas from sticking to the adhesive areas of the backing sheet, particularly when the wings are made by folding them about the peripheral edge and adhesively secured to the backing sheet to create the bias.
We have designed a disposable feminine hygiene article that solves the above-noted problems.
More specifically, in accord with one aspect of the invention, there is provided a disposable feminine hygiene article comprising:
a main body portion comprising an absorbent material and an impervious backing sheet on which the material is mounted, the body portion being bounded by a peripheral edge,
and attachment wings extending from and hingedly attached to the backing sheet along a fold line inside of the peripheral edge, portions of the backing sheet and of the wings being provided with adhesive areas sufficient to bind the article to an undergarment to hold the article in place,
substantially all of the adhesive areas on the wings being offset from the adhesive areas on the backing sheet so that if the wings are properly folded about the fold lines towards the adhesive areas on the backing sheet without an undergarment in place and with any release paper removed, the adhesive areas on the wings cannot contact the adhesive areas on the backing sheet.
In accord with another aspect of the invention, there is provided a method of preventing premature contact of an adhesive area on a wing of a disposable feminine hygiene article, and an adhesive area on a backing sheet of the article, the article further including a main body portion bounded by a peripheral edge, the wing being hingedly attached to the backing sheet along a fold line located inside the peripheral edge and biased to fold along the fold line towards and in contact with the backing sheet; the method comprising the steps:
a) placing the adhesive on the backing sheet in predetermined areas on the sheet, and
b) placing substantially all of the adhesive area on the wing at places that are offset from the predetermined adhesive areas on the backing sheet, so that contact between the wing and the backing sheet due to the bias in the absence of an undergarment, will not place adhesive in contact with adhesive.
In accord with yet another aspect of the invention, there is provided a method of attaching a disposable feminine hygiene article to an undergarment, comprising the steps of:
a) providing the article with a main body of absorbent material mounted on an impervious backing sheet, and opposing wings foldably projecting from the backing sheet to assist in attachment to an undergarment, the backing sheet and the wings each having pressure-sensitive adhesive areas optionally covered with removable release paper, the adhesive areas of the backing sheet occupying at least 50% of the total surface area of the backing sheet, the wings being each foldable towards the backing sheet along a fold line;
b) removing any release paper from all of the adhesive areas;
c) attaching the adhesive area of the backing sheet to one side of a suitable undergarment; and
d) attaching the adhesive areas of the wings to a side of the undergarment opposite to the one side by folding over the wings about the fold lines so that, with the undergarment in-between, substantially all adhesive areas of the wings are offset from the adhesive areas of the backing sheet;
whereby any inadvertent folding over of the wings in the absence of an undergarment will not adhere a wing to the adhesive areas of the backing sheet because the adhesive areas of wings and backing sheet are not superimposed.
As used herein, xe2x80x9csubstantially all adhesive areas are offsetxe2x80x9d means, a deliberate positioning such that the offset condition occurs for all the adhesive areas during normal manufacture and application of the article. It does not mean to exclude the case wherein a negligible amount of the adhesive areas happen to overlap due to either accidental variations during manufacture, or mis-applications during use of the article. As used herein, xe2x80x9cnegligiblexe2x80x9d means, a misplacement of the adhesive and thus an overlap that does not exceed about 5 mm lineal distance.
Also as used herein, a xe2x80x9cfold linexe2x80x9d can be curved or straight, and when referring to the fold line of the wing, it means the line along which the wing is first free to fold relative to the main body. Additionally there may be other portions of the wing more distal from the fold line and the main body, that also are foldable.
Accordingly, it is an advantageous feature of the invention that a disposable feminine hygiene article with back-attached wings is provided that adheres to an undergarment by the use of adhesive areas, so constructed that the adhesive areas of the wings cannot inadvertently and ruinously stick, when exposed for use, to the other adhesive areas in the absence of an undergarment between them.
Other advantageous features will become apparent upon reference to the following Detailed Description, when read in light of the attached drawings.